Indicating device for aerosol container

ABSTRACT

An indicating device for indicating the number of metered doses of medicaments that have been dispensed from or remain in a container having a valve stem extending longitudinally therefrom and moveable between an open and closed position. The indicating device includes a base member adapted to be mounted to the container, a cap member moveably connected to the base member, an indicator member rotatably mounted to the cap member and an indicating mechanism adapted to rotate the counter member an incremental amount upon a predetermined number of axial movements of the cap member relative to the base member. A preferred embodiment of the indicating device includes a ratchet wheel, a drive member selectively engaging the indicating member, a pawl selectively engaging the ratchet wheel, and a non-return member adapted to selectively engage the ratchet wheel so as to maintain a unidirectional rotation of the ratchet wheel. A method for indicating the number of metered doses dispensed from or remaining in the container comprises moving the cap member toward and away from the base member, engaging the ratchet wheel with the pawl and engaging the indicating member with the drive member. A method of assembling an inhalation device including an indicating device is also provided.

This application is a continuation of application Ser. No. 09/073,275, filed May 5, 1998, U.S. Pat. No. 6,082,358 the entire disclosure of which is hereby incorporated by reference herein.

BACKGROUND OF THE INVENTION

The present invention relates generally to an indicating device for indicating the number of metered dosages that have been dispensed from, or remain in, an aerosol container, and in particular, to an indicating device adapted to mount to the aerosol container.

Aerosol dispensing devices have been developed that include a dose indicating device to indicate the number of metered doses that have been dispensed from the device, or to indicate the number of doses remaining therein. For example, patients have certain conditions that can be treated with medicaments dispersed in an aerosol and administered to the patient by inhalation. In one format, the aerosol with medicaments are contained in a container, and dispensed in metered, or measured, dosages with an inhalation device, or actuator boot. In such an arrangement, it can be important for the patient to be able to ascertain the number of metered doses remaining in the container, either by an indication of the number remaining therein or by knowledge of the number already dispensed therefrom, such that the patient is not caught unaware with an empty container when in need of the medicament. Thus, it may be important for the inhalation device to provide an accurate indication of either the number of doses remaining in the container, or the number of doses already dispensed therefrom.

Typically, a conventional aerosol container includes a body and a valve stem which can be depressed relative to the body so as to emit the metered dose of aerosol and medicament. The container is usually supplied with a predetermined number of metered doses, generally on the order of about 200, such that the counting of the number of valve stem depressions, and corresponding number of dispensed metered doses, can be directly correlated with the number of doses remaining in the container.

In operation, the container is typically received within a housing of the inhalation device, wherein the valve is brought into engagement with a support block in the housing. The user administers the medicament by moving the container relative to the housing so as to depress the valve stem and internal valve and thereby release a metered dose, which is typically administered to the user through a port or mouthpiece extending from the housing. After the dose is administered, the valve stem, which is typically spring loaded, biases the container away from the support block so as to again move the container relative to the housing. In this way, a metered dose of medicament is administered by each cycle of linear reciprocal movement of the container relative to the housing.

Some actuator boots, or other devices attached to the medicament container, have indicating devices that convert the linear reciprocal movement of the container relative to the housing into a one-way, or single-cycle, movement of an indicator, wherein the indicator identifies the relative fullness of the container, the number of metered doses remaining therein or the number of doses already administered. Although these actuator boots with indicators, or separate indicator devices, have provided the advantage of generally being able to keep track of the number of dosages, there remains room for improvement. For example, indicating devices of this nature may include complex moving parts which can be difficult to assemble and expensive to manufacture. Such devices may also be susceptible to counting inaccuracies due to the configuration of the indexing or mating parts, or require excessive amounts of space within the housing to accommodate the relatively large or numerous moving parts. Others still may impede or interfere with the airflow and medicament being dispensed from the inhalation device. Alternatively, some devices use electrical circuitry to count or record the dispersements. Such devices can be relatively expensive to manufacture, however, and typically require a power source which may be susceptible to damage in various environments, such as moist conditions.

SUMMARY OF THE INVENTION

Briefly stated, the invention is directed to an indicating device for indicating the number of metered doses that have been dispensed from or remain in a container. The container has a valve stem extending longitudinally therefrom; the valve stem being moveable between a closed position and an open position. The container dispenses a metered dosage when the valve stem is moved to the open position. The indicating device includes a base member adapted to be mounted to the container, a cap member moveably connected to the base member, an indicator member rotatably mounted to the cap member and a drive member adapted to rotate the indicator member an incremental amount upon a predetermined number of axial movements of the cap member relative to the base member.

In a preferred embodiment, the cap member is moveable relative to the base member along an axial path. The indicator member has a plurality of teeth and is rotatably mounted to the cap member about an axis substantially parallel to the axial movement of the cap member relative to the base member. A drive mechanism, including the drive member, comprises a ratchet wheel rotatably mounted to one of the base member and cap member about an axis substantially perpendicular to the axis defined by the axial movement of the cap member relative to the base member. The drive member is coaxially mounted with the ratchet wheel and a pawl is mounted to one of the cap member and base member. The pawl is selectively engaged with the ratchet wheel upon each axial movement of the cap member relative to the base member so as to rotate the ratchet wheel and drive member an incremental amount. The drive member is selectively engaged with at least one of the plurality of indicator member teeth upon a predetermined number of axial movements of the cap member relative to the base member such that the indicator member is rotated an incremental amount.

In another aspect of the invention, a method is provided for indicating the number of measured dosages dispensed from or remaining in the container. The method includes the steps of providing a housing for moveably supporting the container and providing an indicating device having a cap member, a base member and an indicator member rotatably mounted to the cap member. The method further comprises the steps of moving the cap member toward the base member so as to move the container along the longitudinal axis and thereby move the valve stem to the open position wherein a metered dosage is discharged, moving the cap member away from the base member, and moving the indicator member in response to the movement of the cap member relative to the base member.

Referring to the preferred embodiment, the method further includes the steps of engaging the ratchet wheel with the pawl upon one of the movements of the cap member toward and away from the base member and engaging the indicator member with the drive member so as to rotate the indicator member.

In yet another aspect, a method is provided for assembling a dispenser for dispensing metered dosages of medicaments from a container. The method includes the steps of providing a housing, disposing a container in the housing and mounting an indicating device to the container.

The present invention provides significant advantages over other aerosol dispensing devices and indicating devices used therewith. In particular, the indicating device can be separately manufactured and installed as needed on any number of conventional types of aerosol containers with little or no required modification to the container or housing. Moreover, the indicating device with its indicator member and drive mechanism is comprised of a relatively few, simple mechanical parts that are relatively easy to manufacture and assemble. In this way, the indicating device is made more robust and is less susceptible to damage when exposed to various adverse user environments. In addition, the drive mechanism and indicator member provide a reliable indicating device for indicating the number of doses dispensed from or remaining in the container, and the indicating device can be made in a relatively compact configuration that does not interfere with the use of the dispensing device.

The present invention, together with further objects and advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of an indicating device having a viewing window.

FIG. 1A is a top view of the indicating device showing an alternative embodiment of the viewing window with indicia visible therethrough.

FIG. 1B is a top view of the indicating device showing an alternative embodiment of the indicia.

FIG. 2 is a side view of the indicating device being mounted to the top of a container shown in cross-section.

FIG. 3 is a top perspective view of the indicating device with the viewing window positioned in the top of the cap member.

FIG. 3A is a top perspective view of the indicating device with the viewing window positioned along a side portion of the cap member.

FIG. 4 is a bottom perspective view of the cap member with the indicator member mounted therein.

FIG. 5 is an exploded perspective view of the cap member and indicator member shown in FIG. 4.

FIG. 6 is an exploded perspective view of an alternative embodiment of the indicating device, including a base member, a cap member, an indicator member, a ratchet wheel and drive member and a spring.

FIG. 7 is a bottom perspective view of the cap member and indicator member of FIG. 6, with the indicator member mounted in the cap member.

FIG. 8 is an enlarged partial view of the indicator member and cap member of FIG. 7 showing an engagement of the indicator member by the cap member.

FIG. 9 is a bottom perspective assembly view of the cap member, indicator member, ratchet wheel, drive member and spring shown in FIG. 6.

FIG. 10 is an exploded perspective view of the base member and the cap member with the indicating mechanism and indicator member mounted therein.

FIG. 11 is a perspective assembly view of the indicating device shown in FIG. 10.

FIG. 12 is a cross-sectional view of the indicating device taken along line 12—12 of FIG. 11, wherein the cap member is in a fully extended position relative to the base member prior to the application of an axial force by the user.

FIG. 13 is a cross-sectional view of the indicating device similar to FIG. 12 but with the cap member shown as moving toward the base member at an intermediate position of the stroke as indicated by the directional arrows.

FIG. 14 is a cross-sectional view of the indicating device similar to FIG. 12 but with the cap member reaching the bottom of the stroke as indicated by the directional arrows.

FIG. 15 is a cross-sectional view of the indicating device similar to FIG. 12 showing the cap member as it returns to the fully extended position relative to said base member as indicated by the directional arrows.

FIG. 16 is a cross-sectional view of the indicating device taken through the middle of the indicating device and showing engagement members disposed in pockets formed in the base member.

FIG. 17 is a cross-sectional view of the indicating device taken through the middle of the indicating device and showing an alternative return mechanism for the cap member.

FIG. 18 is a bottom view of the assembly of FIG. 9 (without the spring) at initial setting before a first actuation of the indicator device and container.

FIG. 19 is a cross-sectional view taken along line 17—17 of FIG. 16.

FIG. 20 is a bottom view of the assembly of FIG. 9 (without the spring) after the ratchet wheel and drive member have completed one revolution corresponding to a predetermined number of actuations.

FIG. 21 is a cross-sectional view taken along line 19—19 of FIG. 18.

FIG. 22 is an enlarged partial bottom view of the cap member and indicator member showing the indicator member having an indexing member engaging an indentation formed on the cap member.

FIG. 23 is a side view of an alternative embodiment of the indicating device.

FIG. 24 is a top view of the indicating device shown in FIG. 21.

FIG. 25 is a cross-section view of the indicating device taken along line 25—25 of FIG. 24.

FIG. 26 is a cross-section view of the indicating device taken along line 26—26 of FIG. 23.

FIG. 27 is a perspective view of an indicating device with a reset device.

FIG. 28 is a perspective view of an indicating device with an alternative embodiment of the reset device.

FIG. 29 is an exploded view of an alternative embodiment of the indicating device with an alternative embodiment of the reset device and an adapter.

FIG. 30 is a bottom perspective view of the indicating device and adapter shown in FIG. 29.

FIG. 31 is an exploded side view of an indicating device and adapter being applied to the bottom of a container supported in a dispenser housing shown in cross-section.

FIG. 32 is a side view of an indicating device having an adapter applied to the bottom of a container supported in a dispenser housing shown in cross-section.

FIG. 33 is a side view of the indicator member and a lock member in a disengaged position.

FIG. 34 is a bottom view of the indicator member and lock member shown in FIG. 33.

FIG. 35 is a side view of the indicator member and lock member in an engaged position.

FIG. 36 is a bottom view of the indicator member and lock member shown in FIG. 35.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

Referring to the drawings, and in particular FIGS. 31 and 32, an aerosol dispenser is shown as including a housing 200, or actuator boot, and a container 12 disposed therein. The housing has a longitudinally extending cavity 202 shaped to receive the container. A top portion of the housing is generally open such that the container can be inserted in the housing through opening 204 and be installed therein with a bottom end 14 of the container protruding from the housing so as to be exposed to the user for actuation.

The terms “longitudinal” and “axial” as used herein are intended to indicate the direction of the reciprocal movement of the container relative to the housing, and of an indicating device cap member relative to a base member. The terms “top,” “bottom,” “upwardly” and “downwardly” are intended to indicate directions when viewing the inhalation devices as shown in the Figures, but with the understanding that the container is inverted such that the top surface thereof is located adjacent the bottom of the housing and vice versa. Moreover, it should be understood that a user can use the container and dispenser in any number of positions, including but not limited to the preferred upright position shown in FIGS. 31 and 32.

As shown in FIGS. 31 and 32, a cylindrical support block 212 having a well 214 is formed in a bottom portion 206 of the housing. An orifice 210 penetrates the support block to communicate with a bottom portion of the well. In one embodiment, a mouthpiece 208, intended for insertion into the mouth of a patient, forms an exhaust port 216 that communicates with the orifice and well. The mouthpiece 208 extends laterally from the housing so as to facilitate insertion of the mouthpiece into the mouth of the patient.

The container 12 is cylindrical and has a hub 16 disposed on a top surface 17 thereof. A valve stem 18 extends longitudinally from the hub. The valve stem extends coaxially from the container and is biased outwardly therefrom by a spring (not shown) mounted within the valve stem of the container. The container 12 is mounted in the housing by press fitting the valve stem 18 in the well 214 of the support block.

In a preferred embodiment, the container 12 is filled with a pressurized aerosol and medicament which is dispensed therefrom in specific metered doses by depressing or moving the valve stem 18 from an extended closed position to a depressed open position. A single metered dose is dispensed from the container by each reciprocal, longitudinal movement of the valve stem.

In operation, the opening of the valve stem is effected by moving the container 12 reciprocally within the housing 200 along a longitudinal axis, defined by the valve stem and the reciprocal movement of the container, by depressing the bottom end 14 of the container relative to the housing so as to move the valve stem 18 to the open position as it is supported within the well by the support block. As the valve stem is moved to the open position, the container dispenses a metered dose of aerosol and medicament through the well 214 and orifice 210. The aerosol and medicament are then transmitted to the patient through the exhaust port of the mouthpiece by way of either a self-generated or assisted airflow.

In other delivery systems, the housing and holder for the container are attached to a component having a chamber with an output end. Examples of these kinds of delivery systems are shown for example in U.S. Pat. No. 5,012,803, issued May 7, 1991, and U.S. Pat. No. 4,460,412, issued Sep. 11, 1984, both of which are hereby incorporated herein by reference. (No license, expressed or implied, is intended to be granted to either of these patents by reason of the incorporation by reference herein). In these kinds of delivery systems, the component having the chamber can be adapted to receive the mouthpiece of the housing, or it can be integrally connected with a holder supporting the container. In either embodiment, the metered dose of medicament in aerosol is first dispensed from the container into the chamber, and thereafter inhaled by the patient.

In a preferred embodiment, the container 12 is intended to dispense a predetermined number of metered doses of medicament. For example, conventional inhaler containers typically hold on the order of 100 to 200 metered doses. It should be understood, however, that the range of available doses could potentially vary from as few as one dose to as many as 500, or even more, depending, for example, on the capacity of the container, and/or the size of the metering dose valve. In operation, it can be important for the patient to be aware of the number of metered doses remaining in the container such that the patient is not caught unaware with an empty container when in need of the medicament.

Now generally referring to the Figures, a dose indicating device is shown. The indicating device 10 indicates the number of metered doses that have been dispensed from or remain in the container. As shown in the embodiments of FIGS. 1-3A and 10-11, respectively, the indicating device 10, 200, 500 includes a cap member 20, 220, 520 disposed in a base member 40, 540. The base member 40 is configured such that it can be mounted to the bottom of the container 12. In a first embodiment, shown in FIGS. 2, 6 and 12-17, the base member includes a convex, or curved bottom portion 50, or floor, which is shaped to be received in and to mate with the bottom end 14 of the container, which has a concave or inwardly curved contour (see FIG. 2). The base member 40 is preferably bonded to the bottom of the container with adhesive, double sided tape, or similar bonding agent. As shown in FIGS. 6 and 10-15, a circumferential skirt member 94 extends upwardly from the base portion to form a cavity 96.

Alternatively, as shown in FIG. 25, the base member 140 includes a bottom portion 150, a downwardly depending circumferential skirt 152 and an upwardly depending circumferential skirt 156. Depending skirt 152 forms a recess or cavity 154 which is shaped to receive the bottom end of the container. The base member is mounted on the container either by bonding one or more of the bottom portion or skirt to the container, or by press fitting the container in the cavity 154 so as to provide an interference fit between the container and the depending skirt. The upwardly depending skirt 156 and bottom portion form an upper cavity 158 overlying the lower cavity 154.

In yet another embodiment, shown in FIGS. 29-32, an adapter member 90 is attached to one of the above-mentioned base members by way of bonding, an interference fit, a snap fit, or a threadable engagement. The adapter member 90 preferably has a cylindrical configuration and comprises a circumferential skirt 92 that is shaped to receive the bottom end of the container. Again, the adapter can be mounted to the container by way of bonding, an interference fit, or both. Adapters having different internal diameters can be provided such that a single indicating device having a modular base member can be mounted on various aerosol containers having a variety of outer diameters.

Although the disclosed container and indicating device, and in particular, the cap member and base member, are shown as preferably having a circular cross section, those skilled in the art should understand that the container and indicating device, including any adapter, can be configured in other shapes, including for example, but not limited to, a rectangular or triangular cross-section.

As best shown in FIGS. 1, 1A and 1B, the cap member 20 has a top portion 52 with a viewing window 34, 59 formed therein. Preferably, the cap member 20 is circular and the viewing window is formed in the top portion adjacent the outer periphery of the cap member so as to overlie indicia applied to the top of an indicator member supported beneath the cap member. The viewing window can be configured in a number of various shapes. For example, the viewing window 34 can be tapered as shown in FIG. 1, or it can be an arcuate shaped window 59 bounded by coaxial inner and outer curved borders 57, 58 and radial side borders 56 as shown in FIGS. 1A and 1B. The top of the cap member preferably has a plurality of raised portions 54 forming a grippable pattern for the user's thumb, or finger. In this way, the user can firmly press down on the cap member without slippage. One of skill in the art should recognize that other patterns or grippable surfaces, such as a knurled pattern, can be applied to the cap member to facilitate the use of the indicating device.

Referring to FIGS. 4 and 6, the cap member 20, 220 comprises a circumferential skirt 92, 292 depending downwardly from the top portion 52, 252. The skirt preferably has a smaller diameter than the upwardly depending skirt of the base member, such that the cap member skirt- nests within the upwardly extending skirt of the base member. Alternatively, the cap member can be configured with a skirt having a larger diameter than the skirt of the base member such that the base member skirt nests in the cap member skirt. The cap member 20, 220 is moveably mounted to the base member 40 by way of a snap fit.

In particular, as shown in FIGS. 5, 6, 7, 9, 10 and 16, and FIG. 29 the cap member includes a plurality of engagement members 28, 228, 428 extending from an outer circumferential surface of the skirt. The cap member 20, 220, 420 is inserted axially within the recess or cavity 96 of the base member such that the engagement members 28, 228, 428 which have a tapered surface, slide past the rim 42 of the base member skirt until the engagement members are disposed in a plurality of pockets 43 formed along the inner circumferential surface of the base member skirt to form a snap-lock fit. In particular, the upper surface of the engagement member engages an engagement surface 45 defining the top of the pocket. In this way, the cap member is moveable with respect to the base member along an axial, or longitudinal, path. Alternatively, the rim of the base member can be curved slightly inward such that the engagement members engage the inwardly curved rim portion so as to prevent the cap member from being separated from the base member.

The axial movement of the cap member 20, 220 relative to the base member 40 is bounded or constrained by the engagement of the engagement members with the top of the base member pockets (or the base member rim) at a fully extended position and by engagement of a bottom rim 21, 221 of the cap member skirt with the upper surface of the bottom portion at the bottom of the stroke as shown in FIGS. 12-15. One of skill in the art should understand that the engagement members can alternatively be formed on the base member skirt so as to engage pockets or openings, or a rim (or like protrusion), formed on the cap member skirt.

As shown in FIGS. 6, 9, 16 and 17, a spring 100 is disposed between the cap member and the base member. The spring is preferably disposed in a downwardly extending hub portion 30, 230 of the cap member (shown in FIGS. 4 and 6) and an upwardly extending hub portion 44 (shown in FIGS. 10, 16 and 17) of the base member, which are received one in the other. Alternatively, as shown in FIG. 25, a spring 300 is disposed between the cap member and base member and is of such a size that the coils are positioned adjacent the inner circumferential surface of the cap member skirt 392. The spring 100, 300 functions as a return mechanism and biases the cap member 60, 260, 360 upwardly in the base member such that the engagement members 28, 228 of the cap member engage the upper portion of the pockets of the base member. Although a compression spring is shown in the Figures, it should be understood that a belleville washer, cantilever, torsion, leaf and/or tension springs would also work to bias the cap member upwardly into engagement with the base member. The springs can be made of metal or plastic.

As shown in FIGS. 4, 5, 16 and 17, the return mechanism acting between the cap member and base member includes a plurality of resilient arm members 400 extending downwardly from the cap member. As the cap member is moved toward the base member, one or more of the arm members engages a ramped biasing surface 402 formed along an outer portion of the hub portion 44. The ramped biasing surface biases one or more of the resilient arm members outwardly as the cap member moves toward the base member. The resilient arm member(s) act as cantilever springs to bias the cap member away from the base member when the cap member is released by the user. One of skill in the art should understand that the resilient arm members can also be formed on the base member so as to engage a ramped surface formed on the cap member. One of skill in the art should also understand that the spring and resilient arm members can be used together, as shown in FIGS. 16 and 17, or separately.

As shown in FIGS. 4 and 6, a key member 32, 232, or alignment rib, extends radially from the cap member hub portion 30, 230. As shown in FIG. 10, a key hole 44, or slot, is formed in a radially extending portion of the hub portion 44 of the base member. The slot extends radially from the opening in the hub portion. During assembly, the key member of the cap member is received in the key hole of the base member so as to prevent rotation therebetween.

Referring to FIGS. 4-9 and 12-15, an indicator member 60, 260 is rotatably mounted in the cap member 20, 220 about an axis substantially parallel to the axial movement of the cap member relative to the base member. The indicator member is generally open in the middle and includes a top portion 76, 276 having an upper surface 62, 262 that rotatably slides along a bottom surface of the top portion of the cap member. Alternatively, the indicator member can be mounted on the outside of the cap member with a viewing window formed in the indicator member for viewing indicia applied to the top of the cap member.

As shown in the embodiments of FIGS. 5 and 6, the indicator member 60, 260 includes a circumferential skirt 74, 274 depending downwardly from the top portion. Referring to FIGS. 5 and 8, a plurality of protrusions 26, 226, or engagement tab members, extend from an inner circumferential surface of the cap member skirt and engage a rim 64, 264 formed on the bottom of the indicator member skirt. Alternatively, the indicator member can include an engagement member, or rim, that engages a groove or similar opening in the cap member. In this way, the indicator member is secured to the cap member so as to prevent axial movement therebetween but where the indicator member is permitted to rotate relative to the cap member. The indicator member is installed by snap-fitting the indicator member within the cap member. One of skill in the art should understand that the indicator member could alternatively be rotatably mounted on the cap member hub portion (having a portion of the key member cut away), or on a similar axle secured to the cap member.

In yet another alternative embodiment, shown in FIGS. 25 and 26, a plate member 380 holds the indicator member 360 against the inner surface of the top portion 352 of the cap member 320, wherein the spring 300 engages a bottom surface of the plate member 380 to bias a top portion 398 of the plate member against the cap member 320 and the cap member 320 away from the base member. The indicator member 360 is nested in the recess formed between an outer flat portion of the plate member and the bottom surface of the cap member. Referring to FIG. 26, the drive assembly is mounted to the plate member 380 by inserting axle 384 through openings in downwardly extending walls 388 of the plate member. An enlarged portion 396 on the end of the axle engages one of the walls, while the ratchet wheel 382 and drive member 386 are mounted to the other end of the axle to complete the assembly. A top portion of the plate member abuts the cap member.

As shown in the embodiments of FIGS. 4-9, the indicator member 60, 260 has a plurality of inwardly facing teeth 66, 266 formed around the inner circumference of the skirt. As shown in FIGS. 5 and 6, the teeth are preferably formed about only a portion of the circumference.

Alternatively, as shown in the embodiment of FIGS. 25, and 26 the indicator member 360 has a plurality of teeth 366 formed radially inwardly about an inner rim of an opening formed in the indicator member, which is configured as a relatively flat ring that does not include a skirt. In yet another embodiment, shown in FIG. 29, the plurality of teeth 466 extend axially downwardly from a ring-like indicator member 460.

As shown in the embodiment of FIG. 5, the indicator member 60 includes a plurality of indentations 68 formed about the outer circumferential surface of the skirt 74. The cap member includes a pair of upwardly extending resilient indexing members 22, each having an end portion that engages one of the indentations so as to releasably engage the indicator member and prevent rotation therebetween. The angular distance between the indentations 68 is substantially the same as the angular distance between the plurality of indicator member teeth 66. In this way, the indexing member selectively engages the next indentation upon each incremental advancement of the indicator member defined by the distance between adjacent teeth.

Alternatively, as shown in the embodiment of FIG. 6, the indentations and indexing member are reversed, i.e., the indentations 224 are formed about an inner circumferential surface of the cap member skirt and an indexing member 270 depends downwardly from the indicator member in a void formed in the skirt of the indicator member.

In yet another alternative, shown in FIG. 26, the plate member 380 includes a resilient indexing member 370 that engages one of the plurality of teeth 366 to selectively engage the indicator member so as to prevent the inadvertent rotation thereof. Alternatively, the indexing member can extend from the cap member.

As shown in FIGS. 1A and 1B, dosage indicia 72, 172 in the form of numbers or color codings are provided on the top surface of the indicator member and are visible to the user through the viewing window 34, 59 provided in the top of the cap member. Alternatively, as shown in the embodiment of FIGS. 24 and 26, a zero is positioned adjacent a rectangular viewing window 334, preferably by permanent etching, to indicate a multiplication by ten of the indicia visible in the viewing window. One and two digit indicia 372 are formed on the top of the indicator member 360 such that a three digit number is indicated to the user.

In yet another alternative embodiment shown in FIG. 3A, the viewing window 534 is formed in an upper portion of the downwardly depending circumferential skirt 592 of the cap member. The indicia are applied to the outer circumferential surface of the indicator member skirt 574 so as to be visible through the window. In this embodiment, a rim 542 of the base member is preferably scalloped in alignment with the viewing window 534 to provide an unobstructed view of the indicia and to inform the user as to the location of the viewing window.

One of the skill in the art should understand that other indicia indicating the number of doses remaining in or dispensed from the container would include, but not be limited to, various alpha-numerical characters, words, terms or phrases (such as “full” and “empty” ), scales, grids, arrows, raised portions, indentations, color coding and segmentation, shading and like markings, or any combination thereof. For example, a segmented color grid 172 displayed in the viewing window (as shown, e.g., in FIG. 1B) could turn from green, indicating a full container, to yellow, indicating an intermediate capacity, and finally to red, indicating an empty container. It should also be understood that the indicia can be formed integrally with the counter member, or applied thereto by means of paint, dye, etching, pad printing, hot stamping or adhesive labels. When using numerical indicia, the numbers can be arranged to go from 0 (or some beginning number) to the predetermined number of available doses such that a display of that number to the user indicates that the container is empty, or, conversely, to go from the starting predetermined number to 0 (or some ending number), which again indicates to the user that the container is empty.

In a preferred embodiment, the indicator member is made of acrylonitrile butadiene styrene (“ABS”), which is receptive to certain alternative processes of printing or applying the indicia, including pad printing and hot stamping. The cap member and base member are preferably made of a hard plastic material such as Acetel.

Referring to FIGS. 5-9 and 12-18, a drive mechanism is shown as including a drive assembly 80. The drive assembly includes a ratchet wheel 82 coaxially mounted to a drive member on an axle 84. The ratchet wheel, drive member and axle can be made separately, with the ratchet wheel and drive member then mounted on the axle, or all three parts can be integrally molded as a one-piece component. The drive assembly is preferably made of hard plastic material such as Acetel.

The ratchet wheel 82 includes a plurality of teeth 88 (preferably ten) formed around its periphery. Each of the teeth includes an engagement surface 89 and a tapered surface 87. The drive member 86 includes a single tooth 81 extending radially from the axle 84. The drive assembly is mounted to the cap member by engaging opposite ends of the axle 84 with downwardly extending hub portions 36, 236 such that the axle, ratchet wheel and drive member rotate about an axis substantially perpendicular to the axial movement of the cap member relative to the base member and to the axis of rotation of the indicator member. Alternatively, the drive assembly can be mounted to the base member in a similar manner.

As shown in FIGS. 12-15, the drive mechanism further includes a pawl member 48, shown as a flexible rod or finger, which extends upwardly from the bottom portion of the base member and selectively engages one of the teeth of the ratchet wheel. Alternatively, the pawl member can be moveably secured to the cap member and extend through the base member to engage the top of the container, such that the axial movement of the cap member toward the container causes the pawl to move toward the ratchet wheel and engage one of the teeth thereon as described below. A non-return member 238, also shown as a flexible rod or finger, extends downwardly from the top portion of the cap member and selectively engages another of the teeth 88 of the ratchet wheel. It should be understood that the pawl member could alternatively extend from the cap member (and the non-return member from the base member) when the drive assembly is mounted to the base member, as described above.

In operation, as shown in FIGS. 12-21, the user depresses the cap 220 member from a fully extended position (see FIG. 12) toward the base member such that the cap member bottoms out in the base member at the bottom of the stroke (FIG. 14) and such that the base member imparts an axial load on the container until a metered dosage is dispensed therefrom. In a preferred embodiment, the biasing force of the spring 100 (shown in FIG. 6), or alternative return mechanism such as the resilient arm members which act as springs, is less than the biasing force of the spring located in the metering valve of the container such that the cap member first bottoms out in the base member with the container then being moved downwardly in the housing until a metered dose is dispensed.

Referring to FIGS. 12, 13 and 14, as the cap member 220 is depressed toward the base member 40, the pawl 48 selectively engages the engagement surface 89 of one of the ratchet wheel teeth and rotates the ratchet wheel. The tapered surface 87 of one of the teeth formed on the ratchet wheel simultaneously biases the non-return member 238 outwardly until it selectively engages the next tooth near the bottom of the stroke. The user then releases the cap member whereinafter the spring 100 (shown in FIG. 6), or similar return mechanism, biases the cap member 220 away from the base member 40 until the engagement member engages the base portion at the top of the stroke as shown in FIG. 15. When the cap member is released by the user, the container is biased upwardly within the housing along the longitudinal axis such that the valve stem is moved to the closed position within the container. Simultaneously, as the cap member is released and allowed to move away from the base member, the pawl 48 is biased outwardly by the tapered surface 87 of one of the teeth on the ratchet wheel as the non-return member 238 prevents a backwards rotation thereof so as to maintain a unidirectional rotation of the ratchet wheel. At the top of the stroke (shown in FIG. 15), the pawl 48 is again placed in position for selective engagement with one of the teeth of the ratchet wheel. In this way, the ratchet wheel 82, and connected drive member 86 (shown in FIGS. 18-21), are advanced an incremental amount for every actuation of the container and the attendant release of medicament. The incremental amount is defined by and dependent on the number of teeth formed about the periphery of the ratchet wheel. When formed with ten teeth, as shown in the preferred embodiment, the ratchet wheel will make one full revolution for every ten actuations of the indicator device and container, or a tenth of a revolution for each actuation. One skilled in the art will appreciate that the ratchet wheel can be provided with various numbers of teeth formed about its periphery such that the more or less axial movements or actuations of the container are required to make one full rotation of the ratchet wheel.

Alternatively, the operation of the ratchet wheel can be reversed. In this embodiment, the pawl is biased outwardly by the tapered surface of one of the ratchet wheel teeth on the downstroke. At the bottom of the stroke, the pawl is biased into engagement with one of the teeth. When the cap member is released by the patient, the spring, or equivalent return mechanism, biases the cap member upwardly within the base member along the longitudinal axis such that the pawl member engages one of the teeth and thereby rotates the ratchet wheel an incremental amount. In this embodiment, the non-return member maintains the rotational position of the ratchet wheel on the downstroke.

As shown in FIGS. 18-20, the drive member 86 is shown as having a single tooth 81 or segment. Therefore, upon every tenth actuation, the drive member 86 is rotated such that the tooth selectively engages one of the teeth 266 formed on the indicator member so as to rotate the indicator member an incremental amount. The incremental amount of rotation is defined by the distance between adjacent teeth, otherwise defined as the circular pitch of the teeth. In this way, the drive member is selectively engaged with at least one of the teeth of the indicator member after and upon a predetermined number of axial movements of the cap member relative to the base member so as to rotate the indicator member the incremental amount. The predetermined of number axial movements required to cause the indicator member to rotate is defined by and dependent upon the reduction ratio of the ratchet wheel and drive member, which, in turn, is defined by dividing the number of teeth formed on the ratchet wheel by the number of teeth formed on the drive member. For example, as shown in the preferred embodiment, a ratchet wheel having ten teeth and a drive member having one tooth will result in an incremental movement of the indicator member, otherwise defined as the advancement of one tooth of the indicator member, upon every ten axial movements. Similarly, if the drive member had four teeth, and the ratchet wheel twenty, the predetermined number would equate to five axial movements, and so on. A one-to-one gear ratio would result in a predetermined number of one axial movement, wherein the indicator member would be moved upon every axial movement.

Referring to FIG. 19, the indicator member 260 and drive member 86 are shown prior to an initial actuation or use by the user. In particular, the drive member tooth is positioned adjacent the first tooth 266 on the indicator member. In this embodiment, wherein the ratchet wheel comprises ten teeth, ten actuations are required before the tooth 81 engages the first tooth 266 on the indicator member as shown in FIG. 21. At this point, the indicator has completed a single cycle equal to the number of predetermined number of axial movements, which results or culminates in the incremental movement of the indicator member. The cycle is then repeated (by again making the predetermined number of axial movements) so as to again culminate in the incremental movement of the indicator member. Preferably, as shown in FIGS. 1A, 3A, 24 and 26, numerical indicia (including numbers and dots) are applied in increments of ten to correlate to the preferred embodiment requiring ten axial movements for one incremental advancement of the indicator wheel.

The ratchet wheel and drive member with their reduction ratio provide a simple but reliable mechanism for advancing the indicator member. In particular, the indicator member can be made with fewer teeth than if it were required to advance upon every actuation of the indicator member and container. For ease of manufacturing, it is desirable to provide as coarse a pitch on each of the indicator member and ratchet wheel as possible, although the gears are still defined as fine-toothed gears. However, it is also intended that the indicator member make only a single revolution (single-cycle) corresponding to a complete evacuation of medicament from the container. Thus, when a large number of doses (on the order of 200 or more) are contained within the container, it is important for the ratchet wheel and drive member to provide a relatively high reduction ratio, such that 200 linear reciprocal movements of the cap member and container correspond to one or less revolutions of the indicator member. As such, the indicator member can be made with coarser teeth at less cost. In addition, larger coarser teeth interacting with a relatively large drive member tooth helps to improve the accuracy of the device as those parts mesh. In addition, the mechanism, and its attendant reduction ratio, permits the indicator member to make only a single revolution during the life of the container, i.e., until it is emptied, even when the container contains a relatively large number of metered doses (on the order of 200 or more doses).

Where, as shown in FIG. 5, the teeth 66 extend only partially around the periphery of the indicator member, the indicator member 60 is not advanced after the drive member engages the last tooth, even when the cap member is repeatedly moved to actuate the container. This ensures that the indicator member cannot be advanced past the last indicia indicating that the container is empty to a first indicia indicating that the container is full, so as to confuse the user.

Alternatively, as shown in FIGS. 33-36, the indicating device includes a lock device. In particular, the base member includes a first lock member 702, configured as a post member extending upwardly from the bottom of the base member. The indicator member 760 includes a second lock member 704, shown in FIG. 35 as an extension of one of the plurality of teeth 766 formed around the circumference of the indicator member. In operation, the cap member is moved towards and away from the base member as described above so as to rotate the indicator member. During this operation, as shown in FIGS. 33 and 34, the first lock member 702 is positioned inside the inner diametrical surface of the plurality of teeth so as to not interfere therewith as it is moved into the recess formed by the indicator member as shown in FIG. 33. After the indicator member has made one complete rotation, which preferably correlates to an emptying of the container, the second lock member 704 is rotated over the first lock member 702 as shown in FIGS. 35 and 36. In this position, the cap member cannot be moved toward the base member and the user is thereby prevented from further discharging, or attempting to discharge, an empty container. The immobility of the cap member also provides a secondary indicia that the container is empty. One of skill in the art should understand that the size and shape of the first and second lock members can be varied. For example, a post member may extend from the cap member so as to engage a stepped surface in the base member.

As shown in FIGS. 29 and 30, a reset wheel 106 is coaxially mounted with the ratchet wheel 82 and drive member 86. The outer periphery 108 of the wheel, which includes a plurality of teeth for gripping by the user's thumb, is exposed as it extends through the bottom surface 50 of the base member. One of skill in the art should understand that the reset wheel can be exposed by extending from other portions of the indicator device for access by the user. The user rotates the reset wheel 106 to manually rotate the indicator member to its original starting position, or any other desired setting, without having to move the cap member relative to the base member. In this way, the indicator member can be recycled for use on a new container, or can be moved to the proper setting prior to installing the indicating device on the container. In this way, the same indicating device can be used with various containers containing varying numbers of metered dosages of medicament. During the movement of the indicator wheel relative to the cap member, the force of the indexing member against the indentations in one of the cap member and indicator member is overcome such that the indexing member repeatedly moves into and out of engagement with the indentations as the indicator member is rotated by the user to the desired setting. This movement is similar to the movement of the indexing member occurring upon each incremental advancement of the indicator member relative to the cap member.

Preferably, the reset wheel is used with an indicator member having teeth formed about its entire periphery, such that the indicator wheel need only be moved a few teeth (one or more) to return it to the zero (or full, e.g., 200) position. The reset wheel can be used with or without the lock device described above, since the wheel can be used to move or rotate the indicator wheel independent of any axial movement between the cap member and base member.

In an alternative embodiment shown in FIG. 28, a reset selector member 602 is mounted to the end of the axle and is exposed in an opening 604 in the side or skirt 694 of the base member. The reset selector member 602 is mounted on the axle. The selector member 602 is provided with a slot adapted to receive the head of a screw driver or like tool, which can be actuated by the user to rotate the axle, coaxially mounted drive member and indicator member until the desired indicia are visible in the viewing window. This feature can be valuable for resetting an indicating device for use on a new container, or for initially setting the device for the proper number of doses contained in the container. One of skill in the art should understand that recesses and/or protrusions other than the disclosed slot can be exposed on the selector member to allow the user to grip or otherwise operably engage the selector member and to thereafter rotate the indicator member. One of skill in the art should also understand that the opening in the base member could be positioned anywhere along the longitudinal path of the axle as the cap member moves relative to the base member so as to expose the selector member when aligned with the opening.

In yet another alternative embodiment, shown in FIG. 27, a selector window 806 is formed in the top of the cap member. A reset selector member 802, configured as a protrusion or like grippable member, is exposed in the window as the indicator member is rotated to the empty position. In one embodiment, as described above, the plurality of teeth are formed only around a portion of the periphery of the indicator member so as to leave a gap between the first and last tooth. In such an embodiment, the selector window 806 is preferably of such length that the user can move the reset selector member 802 within the window until the first tooth is again in position for engagement with the drive member. It should be understood, however, that the reset selector member can also be used with an indicator member having teeth formed around the entire periphery of the member.

In an alternative embodiment, a plurality of reset members, or a similar grippable surface, configured for example as a plurality of notches or teeth, can be formed around the entire periphery of the indicator member and exposed in a selector window, or alternatively, in the viewing window. In such an embodiment, the indicator wheel can be rotated to expose different indicia at any time simply by engaging the reset selector members on the indicator member with the user's thumb or like member.

In yet another embodiment, shown in FIG. 24, an opening, or selector window 906, is provided in the top of the cap member. A thin tool, such as a paper clip, is inserted through the opening to bias the resilient indexing member 370 out of engagement with the indicator member. The user can then operably engage the indicator member with their finger or the like, either through the viewing window or a selector window, to move the indicator member to the desired setting.

Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. As such, it is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is the appended claims, including all equivalents thereof, which are intended to define the scope of the invention. 

What is claimed is:
 1. An indicating device suitable for indicating the number of metered dosages that have been dispensed from or remain in a container, said indicating device comprising: a base member; a cap member moveably connected to said base member, said cap member moveable relative to said base member along an axial path between at least a first and second position; a resilient cantilevered member extending from one of said base member and said cap member; and a ramped surface, wherein at least a portion of said resilient cantilevered member engages and is moveable along said ramped surface in a first direction as said cap member is moved from said first position to said second position, wherein said ramped surface biases said resilient cantilevered member to a flexed condition as said cap member is moved relative to said base member from said first position to said second position, and wherein said at least said portion of said resilient cantilevered member engages and is moveable along said ramped surface in a second direction opposite said first direction as said cap member is moved from said second position to said first position.
 2. The invention of claim 1 wherein said cap member is moved towards said base member along said axial path as said cap member is moved between said first and second positions.
 3. The invention of claim 1 wherein said resilient cantilevered member extends from said cap member and said ramped surface is formed on said base member.
 4. The invention of claim 1 wherein said resilient cantilevered member extends in the direction of the axial movement of said cap member relative to said base member.
 5. The invention of claim 1 wherein one of said cap member and said base member comprise a plurality of said resilient cantilevered members.
 6. The invention of claim 1 wherein said ramped surface is formed on the other of said base member and said cap member.
 7. The invention of claim 1 wherein said at least said portion of said resilient cantilevered member comprises an end portion thereof.
 8. The invention of claim 7 wherein said ramped surface slopes away from said end portion of said resilient cantilevered member when said cap member is in said first position.
 9. The invention of claim 1 further comprising said container attached to said base member.
 10. The invention of claim 1 further comprising an indicator member rotatably mounted to one of said cap member and said base member.
 11. The invention of claim 10 wherein said indicator member is rotatably mounted to said cap member.
 12. An indicating device suitable for indicating the number of metered dosages that have been dispensed from or remain in a container, said indicating device comprising: a base member; a cap member moveably connected to said base member, said cap member moveable toward and away from said base member along an axial path; a resilient arm member extending longitudinally from one of said base member and said cap member in a direction parallel to the axial path defined by the movement of said cap member relative to said base member, wherein said resilient arm member comprises an end portion; and a ramped surface formed on the other of said base member and said cap member, wherein said end portion of said resilient arm member engages said ramped surface and is progressively displaced by said ramped surface as said end portion moves along said ramped surface as said cap member is moved toward said base member, and wherein said end portion moves along said ramped surface as said cap member is moved away from said base member.
 13. The invention of claim 12 wherein said resilient arm member extends from said cap member and said ramped surface is formed on said base member.
 14. The invention of claim 12 wherein one of said cap member and said base member comprise a plurality of said resilient arm members.
 15. The invention of claim 12 wherein said ramped surface slopes away from the end portion of said resilient arm member.
 16. The invention of claim 12 wherein said ramped surface defines a plane.
 17. The invention of claim 12 further comprising an indicator member rotatably mounted to one of said cap member and said base member.
 18. The invention of claim 17 wherein said indicator member is rotatably mounted to said cap member.
 19. The invention of claim 12 further comprising said container connected to said base member.
 20. A method for indicating the number of metered dosages dispensed from or remaining in a container comprising: applying a force to a cap member moveably connected to a base member; moving said cap member toward said base member along an axial path in response to said applying said force; moving at least a portion of a resilient cantilevered member along a ramped surface in a first direction as said cap member is moved toward said base member, displacing said at least said portion of said cantilevered resilient member with said ramped surface as said at least said portion of said resilient cantilevered member moves in the first direction and thereby progressively flexing said resilient cantilevered member, wherein said resilient cantilevered member extends from one of said base member and said cap member; releasing said cap member from said force; and biasing said cap member away from said base member by moving said at least said portion of said resilient cantilevered member along said ramped surface in a second direction opposite said first direction and thereby progressively unflexing said resilient cantilevered member.
 21. The invention of claim 20 wherein said resilient cantilevered member extends from said cap member and said ramped surface is formed on said base member.
 22. The invention of claim 20 wherein said resilient cantilevered member extends in a direction parallel to the axial path defined by the movement of said cap member relative to said base member.
 23. The invention of claim 20 wherein one of said cap member and said base member comprise a plurality of said resilient cantilevered members.
 24. The invention of claim 20 wherein said ramped surface is formed on the other of said base member and said cap member.
 25. The invention of claim 20 further comprising dispensing a dosage from a container attached to said base member as said force is applied to said cap member.
 26. The invention of claim 20 further comprising rotating an indicator member about an axis running substantially parallel to said axial path in response to said force being applied to said cap member, wherein said indicator member is rotatably mounted to one of said cap member and said base member.
 27. The invention of claim 26 wherein said indicator member is rotatably mounted to said cap member. 